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Approximate Exponential Integrators for Time-Dependent Equation-of-Motion Coupled Cluster Theory
David B Williams-Young1, Stephen H Yuwono2, A Eugene DePrince Iii2
1Applied Mathematics and Computational Research Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States.
Journal of Chemical Theory and Computation
|December 12, 2023
Summary
New methods for simulating quantum systems offer superior accuracy and efficiency. These time-domain simulations are crucial for advancing electronic structure theory and understanding complex many-body systems.
Area of Science:
- Quantum chemistry
- Computational physics
Background:
- Accurate time-domain simulations of correlated many-body systems are essential in modern electronic structure theory.
- Developing efficient and stable integration schemes for the time-dependent Schrödinger equation is a key challenge.
Purpose of the Study:
- To present two novel approaches for forming the quantum propagator in time-dependent equation-of-motion coupled cluster theory.
- To evaluate the performance of these new methods against existing techniques.
Main Methods:
- Utilizing Chebyshev and Arnoldi expansions of the complex, nonhermitian matrix exponential.
- Comparing the proposed algorithms with the Lanczos method, fourth-order Runge-Kutta, and exact dynamics.
Main Results:
- Both proposed integration schemes demonstrated superior accuracy compared to reference methods.
- The new methods also showed enhanced efficiency in the studied test cases.
Conclusions:
- The developed Chebyshev and Arnoldi-based propagator formation methods provide accurate and efficient solutions for time-dependent Schrödinger equation simulations.
- These advancements are significant for the field of electronic structure theory and quantum dynamics.
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